This report highlights recent initiatives to inspire policy action at a time wheninnovation leadership by the public and private sectors is critical to meeting thenet zero challenge. Countries around the world strive to become home to the nextmajor company emerging from a start-up with a disruptive clean energy invention,and with good reason. Whilst aiding innovation in support of climate and energygoals, nurturing innovative start-ups to maturity can also create local economicprosperity because clean energy transitions will be a major market opportunity forall countries, all century long. Already, the number of government policy measuresto help start-ups get new clean energy technologies to market has risen sharplysince the Paris Agreement was signed in 2015. This is extremely encouraginggiven that energy technology start-ups continue to face challenges attractingpatient capital and governments possess some unique resources to speed themthrough the phases to reach technical maturity while staying in business. Basedon 14 detailed case studies and in-depth interviews, this report presents a rangeof impressive policy measures from a variety of different country contexts, andidentifies eight key insights for effective policy to support clean energy start-ups.